Braking mechanism for sleds



Dec. 27, 1960 H. LIPLUMB 2,966,364

' BRAKING MECHANISM FOR sLEDs Filed March 27, 1957 4 Sheets-Sheet 1 INVENTOR ATTORNEY Dec. 27, 1960 H. L; PLUMB BRAKING MECHANISM FOR susns 4 Sheets-Sheet 2 Filed March 27, 1957 mm EN BY WA ATTORNEY Dec.- 27, 1960 H. L. PLUMB 2,966,364

BRAKING MECHANISM FOR SLEDS Filed March 27, 1957 4 Sheets-Sheet 3 INVENTOR BY MR ATTORNEY Dec. 27, 1960 H. LPLUMB 2,966,364

BRAKING MECHANISM FOR SLEDS INVENT OR BY MN kid,

ATTORNEY BRAKING MECHANISM F OR SLEDS Howard L. Plumb, Bethesda, Md. (121 Choate Lane, Pleasantville, N.Y.)

Filed Mar. 27, 1957, Ser. No. 648,972

14 Claims. (Cl. 280-22) The present invention relates to sleds, and more particularly to braking means therefor, and is a continuationin-part of my copending application Serial No. 641,662, filed February 21, 1957 now abandoned.

A principal object of the invention is to enhance the safety of sleds, particularly those intended for use by children, by providing improved mechanism by which the speed of the sled can be reduced under control of the occupant and by which the sled can be brought to a halt at will.

A related object is to provide braking mechanism which will involve no projection or protuberance that might constitute a hazard likely to result in injury to the body of an occupant especially when being upset or thrown by momentum or otherwise over the surface of the sled.

Another object is to combine braking means with more or less conventional steering mechanism without appreciably or noticeably increasing or extending the operating instrumentalities, so that a dirigible sled can be slowed down or brought to a stop at the will of the occupant without requiring the handling or operation of any more actuating means than those already present in the steering apparatus.

A further object is to provide braking mechanism of the kind indicated which is of simple construction and can be produced inexpensively in rugged and durable elements and combinations and which will be unfailingly operative and foolproof in use.

With the foregoing and other objects in view, the invention comprises, in certain forms of embodiment which are at present preferred, the combination of parts and features which are depicted in the accompanying drawings, in which Figure l is a top plan view of one embodiment of the invention;

Fig. 2 is a side elevational view of the embodiment shown in Fig. 1;

Fig. 3 is a front elevational view of the same;

Fig. 4 is a detail top plan view of the front portion of the same embodiment, with certain of the structure shown in horizontal cross section;

Fig. 5 is a vertical longitudinal sectional view through slightly more of the front portion than is shown in Fig. 4;

Fig. 6 is a vertical longitudinal sectional view, corresponding to that of Fig. 5, but showing a modified form of the invention;

Fig. 7 is a bottom plan view of the structure shown in Fig. 6;

Fig. 8 is a detail vertical cross sectional view taken on the line 8-8 of Fig. 6;

Fig. 9 is a top plan view of a further modified form of the invention;

Fig. 10 is a vertical longitudinal sectional view taken on the line 10-10 of Fig. 9; and

Fig. 11 is a detail vertical cross sectional view taken on the line 1111 of Fig. 10.

Generally speaking, the invention comprises mounting a brake shoe, or a pair of brake shoes, on the body of a sled for movement between retracted, inoperative position and projected, operative position, preferably but not 2,966,364 Patented Dec. 27, 1960 necessarily about a pivot axis, and providing actuating means for such movement in the form of a hand grip, or a pair of hand grips, one for each shoe, operable independently of each other or dependently and simultaneously, said hand grips being substantially cylindrical portions of a transversely extending bar in the form of a rod which are rotatable about the axis of the rod and which are preferably the hand grips by which the rod is pulled obliquely from its normal position of rightangularity to the longitudinal axis of the sled body in the operation of steering the sled.

Three presently preferred forms of embodiment of the invention are depicted in the drawings in order to exemplify the inventive principles. These disclosures are given as illustrative and with no intention of restricting the claims to the details of the selected forms of construction. On the contrary, the principles of the invention are capable of being embodied in other and further modified forms all of which, to the extent that they incorporate the principles pointed out by the broader of the appended claims, are to be deemed within the scope and purview thereof.

Referring now to the drawings, and first to Figs. 1 to 5, inclusive, the reference numeral 1 designates the body of a sled of conventional type having a pair of side rails 2, 2 connected by cross members 3, 3 which are mounted on legs 4 upstanding from a pair of longitudinally extending runners 5, 5. At the forward end of the sled a cross bar, generally designated 6, is mounted at about the level of the body so as to extend transversely of the body with its ends projecting laterally beyond the body, i.e., outwardly beyond the respective side rails 2, 2, as best shown in Figs. 1 and 3.

In the type of sled selected for illustration in Figs. 15 the cross bar 6 functions as a steering bar or handle, and to this end the runners are made somewhat flexible and the bar 6 is connected to the runners for flexing them, when the bar is pulled from its normal position of right angularity to the longitudinal axis of the sled body, shown in the several figures, to a position of oblique angularity thereto, so that the front portions of the runners will be curved in parallelism to the right or the left, thus causing the moving sled to turn in one direction or the other. In the Figs. 1-5 construction the fronts of the runners are upwardly curved and their terminals are pivoted at 7, 7 to metallic extensions 2a of the side rails 2 and to a connecting link 8; the center of this link is pivoted at 9 to the front end of a pair of superposed lengths of strap iron rigidly secured together to form a lever 10 which lies in the line of the axis of the sled body and has its rear end fulcrumed at 11 to a point on the front of the body. It is to an intermediate point on this lever that the center of the bar 6 is rigidly secured, as by means of the rivets or bolts shown at 12. It will be evident that when the bar is pulled to an oblique position the lever 10 fulcrums about the pivot 11 to swing the pivot 9 to one side or the other of the axis of the body, thus shifting the link 8 sidewise and consequently correspondingly moving the front ends of the tunners simultaneously, in parallelism to the right or left, the side rail extensions 2a bending with the runners. This arrangement, functioning in this manner to effect steering of the sled, is well known and forms part of the present invention only to the extent that the new braking mechanism provided by the invention can be incorporated in the steering mechanism, utilizing much of the structure already provided for steering and adding a minimum'of new parts. This arrangement will now be described in its application to the Figs. 15 embodiment of the invention.

The brake element of this form of the invention comprises a shoe, generally designated 20, best made of stout strap iron having a rear portion 21 intended to make friction, rubbing or digging contact with the ground, i.e., the snow or ice surface over which the sled may be moving when it is to be slowed down or stopped, and having also a forward portion 22 which makes an obtuse angle with the rear portion, all as best shown in Figs. 2 and 5. To increase the friction of the engagement of the rear portion 21 with the ground, the lower face of that portion may be specially formed, as with the serrations shown at 23. The forward portion 22 of the shoe terminates in an integral connection with a tubular sleeve, hereinafter designated a grip portion 24 of the bar 6, which is journaled on the bar for free rotation about the axis thereof. As best shown in Fig. 4, the grip portion 24 may be mounted on the bar 6 by sleeving it over a cylindrical portion of the bar and holding it against axial movement by means of a collar 25 secured by a setscrew 26 on the bar at the inner end of the grip portion 24 and a cap nut 27 screwed onto the threaded outer end of the bar. To facilitate rotation of the grip portion 24 on the bar 6, the outer end portion of the grip portion may have splined or otherwise non-rotatably fixed on it a handle element 28 preferably of rubber, leather or analogous material like that used for the grips of bicycle handle bars.

The structure that has just been described is best duplicated at the two sides of the sled, so that two brake shoes and two actuating means are provided, as shown in Figs. 1, 3 and 4. It will be understood that each of the shoes is independently movable by turning the corresponding grip portion 24 of the bar 6 since the bar is not rotated, being in fact flattened centrally at 29 in the region of the rivets or bolts 12. Thus it is possible to actuate both brake shoes simultaneously to slow or stop the sled while it continues to move in a straight line, or only one of the shoes may be actuated, or one may be applied to a greater extent than the other, in this way causing the sled to tend to turn.

The shoes are kept normally in retracted position, with the portions 21 above the level of the runners by some such means as the springs 30 which in the illustrated embodiment of the invention are coil tension springs each having one end hooked into the adjacent brake shoe portion 21 and the other end anchored to a point on the sled body, such as the adjacent cross member 3, as shown in Fig. 5.

Figs. 6-8 illustrate a modification in which the grip portions 40 of the cross bar 41, which may be provided with handle elements 42, are solid, integral parts of the bar. Hence they are necessarily rotated together, the bar turning in a bearing 43 formed in a lever 44 in which the reduced central cylindrical portion 45 of the bar is journaled, the arrangement, best shown in Fig. 7, being such that swinging the bar to oblique relationship with the body axis will swing the lever to one side or the other about its fulcrum 46 on the body 47 of the sled so as to shift the front cross connecting link 48 and thus flex the runners 49 that are connected to this link. It is believed that the construction and manner of functioning will be understood from the showings in the figures and from the analogy to the operation of the Figs. 1-5 embodiment of the invention.

Rotation of the bar 41 actuates the brake shoes 50 through the medium of a crank arm 51 which depends radially from the bar 41, extending through a slot 52 in the bottom of the bearing 43. To the outer end of this crank arm are fixed the ends of a pair of cables 53, 56 which extend through flexible tubing 54 strung along the under side of the sled body 47 in the manner of Bowden wires and have their rear ends fastened to the front portions of the respective brake shoes 50, as best shown in Fig. 6. Each of these shoes may be a simple lever of the first order, pivoted more or less centrally at 55 to one of the legs 56 by which the body is mounted on the runners 49. The wires 53, while sufliciently flexible to move freely through the curved tubing 54, are nevertheless stitr' enough to move the'shoes 50 in both projecting and retracting directions, so that no springs are needed for retraction. However, if desired or thought necessary it is a simple matter to install retraction springs like those shown at 30 in the Fig. 5 embodiment of the invention.

Figs. 9-11 show a further modification illustrating a construction which combines certain of the features of the two previously described species of the invention and adds some features which may, within the broad principles of the invention, be incorporated in those species. In this form the cross bar 60 is of solid or tubular one-piece construction with a reduced central portion 61 of round cross section which is journaled in the bearing 62 provided by oppositely rounded half-bearing bulges formed in the two metal strips which constitute the lever 63. This lever is pivoted to the connecting link '64 by the pin 65 and is similarly pivoted to the forward portion of the body by a pin 66.

A brake member, such as the shoe 67, which may be substantially and generally like the shoe 20 of the first described embodiment of the invention, extends radially from the cross bar 66 at each side of the journal 61, as by being welded to the cross bar, and these two shoes are held normally retracted by a coil spring 68 which extends under tension between the pin 66 and a pin 69 which depends radially from the cross bar 60 adjacent to the journal portion 61. Alternatively, if desired, the arrangement may be altered slightly by slotting the lower strip member of the lever 63 in the bearing bulge and projecting the pin 69 through such slot, thus centering the spring 68. The shoes 67 may be provided with serrated operating faces like those of the shoes 20, or they may be made generally smooth and/or formed with a single tooth 70 as shown in Fig. 10. In this connection it is to be understood that the specific design of the operative faces of the shoes forms no part of the invention, broadly considered, and may be varied widely.

It will be evident that rotation of the cross bar 60 in its bearing 62 will tension the spring 68 and apply the brake shoes 67 by swinging them down into contact with the ground, in the same way that is accomplished by rotation of the cross bar 41. In order to increase the leverage involved in this rotation, and to augment the mechanical advantage of the movement, the cross bar 60 may be bent backwardly at its terminal portions to provide obliquely rearwardly directed grip ends 71. With this feature of construction, which obviously may be incorporated in the cross bar 41 as well, rotation of the cross bar is accomplished by the occupant of the sled pushing down on the grip ends. The effective length of the lever constituted by each grip end is made sufficiently short to produce good digging penetration of the tooth 70, or equivalent surface of the shoe, into the ground" before the ends of the grips are objectionably close to the ground. The normal position of the grips, with the spring 68 holding the shoes 67 retracted, is best arranged to be substantially horizontal, i.e., in the same horizontal plane that includes the straight central portion of the cross bar.

It is believed to be evident that an important advantage of the invention is the provision of actuating means for a brake shoe, or for a pair of brake shoes, which is operated by the simple expedient of rotating a member which is not upstanding from the body of the sled and does not constitute a hazardous projection capable of inflicting bodily injury on an occupant in the case of a spill or an upset or some movement of the occupant relative to the sled, as by momentum or inertia. In most cases, as will be understood, the actuating means is a member, or a portion of a member, which is already present on the sled as part of the steering mechanism, so that in such types of sleds very little has to be added to provide the safe brake of the invention, which I regard as an advantage of considerable importance. In other cases, within the principles of the invention as defined by the broader of the appended claims, the actuating means may be a bar used solely for that purpose, having no steering function, which Will be the form the invention may taken when applied to a sled having runners that are not flexible or are not jointed or otherwise designed to make the sled dirigible.

The invention may be incorporated in other and further modified forms within the broad principles hereinabove explained, and all such embodiments, to the ex- .tent that they are within those principles, are to be deemed within the scope and purview of the appended claims.

I claim:

1. In combination with a dirigible sled comprising a body surmounting a pair of spaced parallel longitudinal runners, steering bar means extending transversely of the body and comprising a central shaft portion and having end grip portions projecting laterally beyond the body, means mounting the bar means on the body for rocking movement of the shaft portion in a horizontal plane about a vertical pivot axis responsive to pushing and pulling stresses on the grip portions and for rotation of at least one of the grip portions for rotation of said grip portion about the axis of the shaft portion, means connecting the bar means to the runners for causing the runners to deviate laterally for steering the sled when the bar means is rocked about said pivot axis, braking means comprising a shoe mounted on the sled for movement between a normally retracted position above the level of the runners and an operative position projected below said level, and means connecting the shoe to the rotatable grip portion for projecting the shoe responsive to rotation of said grip portion.

2. The combination claimed in claim 1, including a spring connected to the shoe and the body for holdng the shoe normally retracted and yieldable on rotation of the rotatable grip portion for projection of the shoe.

3. The combination claimed in claim 1, in which both of the projecting grip portions are rotatable and including a pair of shoes, one shoe and one grip portion being connected together at each side of the body.

4. The combination claimed in claim 1, in which bo'h of the projecting grip portions are rotatable and including a pair of shoes, one shoe and one grip portion being connected together at each side of the body, and each shoe and its connected grip portion being operable independently of the other shoe and its connected grip portion, whereby the direction of movement of the sled may be altered by projecting one shoe more than the other.

5. The combination claimed in claim 1, in which the shoe is directly and rigidly connected to the rotatable grip portion.

6. The combination claimed in claim 1, in which the shoe is a bar having two angularly related end portions, one of said portions having its end directly and rigidly connected to the rotatable grip portion and radiating therefrom and the other being provided with a friction surface for engagement with the surface on which the sled is moving.

7. The combination claimed in claim 1, in which both of the projecting grip portions are rotatable and including a pair of shoes, one shoe and one grip portion befng connected together at each side of the body, and the two grip portions being rigidly connected together for simultaneous and equal actuation of the two shoes.

8. The combination claimed in claim 1, in which the steering bar means is a shaft journaled on the body with the grip portions solid thereon, said steering bar means being provided with a crank arm, and flexible line means connecting the shoe to the crank arm.

9. The combination claimed in claim 1, in which the steering bar means is a shaft journaled on the body with the grip portions solid thereon, said steering bar means being provided with a crank arm, and including a pair of shoes, one at each side of the sled and each connected by a flexible line to the crank arm.

10. In combination with a dirigible sled comprising a body surmounting a pair of spaced parallel longitudinal runners having laterally flexible forward portions, steering bar means extending transversely of the forward portion of the body and having integral portions projecting laterally beyond the body and terminating beyond the body in angularly rearwardly directed terminals constituting grip portions, means pivotally mounting the bar means on the body for rocking movement in a horizontal plane about a vertical pivot axis responsive to pushing and pulling stresses on the grip portions and journaling the bar means for rotation about the axis of the bar means, means operatively connecting the bar means to the laterally flexible forward portions of the runners for causing the runners to deviate laterally for steering the sled when the bar means is rocked about said pivot axis, and braking means comprising a shoe having its forward end rigidly connected to the bar means and terminating rearwardly in a free end portion movable on rotation of the bar means between a normally retracted position above the level of the runners and an operative position projected below said level into braking engagement with the surface on which the sled is moving.

11. The combination claimed in claim 10, in which the bar means includes a central reduced portion of round cross section constituting a journal, and in which the sled includes a bearing mounting said journal for rotation about the axis of the bar means to move the shoe into operative and retracted positions.

12. In combination with a dirigible sled comprising a body surmounting a pair of spaced parallel longitudinal runners having laterally flexible forward portions, steering bar means extending transversely of the forward portion of the body having a central portion and end grip portions projecting laterally beyond the body and being angularly related to the central portion, said central portion being of round cross section constituting a journal, a bearing on the body mounting said journal for rotation of the bar means, means pivotally mounting the bar means n the body for rocking movement in a horizontal plane about a vertical pivot axis responsive to horizontal pushing and pulling stresses on the grip portions, means operatively connecting the bar means to the laterally flexible forward portions of the runners for causing the runners to deviate laterally for steering the sled when the bar means is rocked about said pivot axis, braking means comprising a shoe mounted on the sled for movement between a normally retracted position extending above the level of the runners and an operative position projected below said level into braking engagement with the surface on which the sled is moving, and means connecting the shoe to the bar means for projecting and retracting the shoe upon rotation of the bar means responsive to vertical pushing and pulling stresses on the grip portions.

13. The combination claimed in claim 12 in which the shoe is directly connected to the bar means and extends radially therefrom.

14. The combination claimed in claim 12 in which the braking means comprises a pair of shoes extending radially from the bar means at separated points spaced apart along the axis thereof.

References Cited in the file of this patent UNITED STATES PATENTS 642,124 Holdsworth Jan. 30, 1900 1,310,252 Seifert July 15, 1919 1,516,941 Winn Nov. 25, 1924 2,188,030 Berthiaume Jan. 23, 1940 2,499,639 Forseth Mar. 7, 1950 2,664,174 La Marr Dec. 29, 1953 

